Automatic casting apparatus



Sept. 18, 1956 R. DOAT 2,763,041

AUTOMATIC CASTING APPARATUS Filed Jan. 27, 1954 5 Sheets-Sheet l F/E.1a

INVENTOR. Ross RT 9 on 7- Sept. 18, 1956 R. DOAT 2,763,041

AUTOMATIC CASTING'AFPARATUS Filed Jan. 27, 1954 5 Sheets-Sheet 2 IF jFIE. 1b.

INVENTOR. ROBERT DOA? Sept. 18, 1956 R. DOAT AUTOMATIC CASTING APPARATUS5 Sheets-Sheet 3 Filed Jan. 27, 1954 INVENTOR. ROBERT DoA'r Sept. 18,1956 R. DOAT AUTOMATIC CASTING APPARATUS 5 Sheets-Sheet 4 Filed Jan. 27,1954 Sept. 18, 1956 R. DOAT AUTOMATIC CASTING APPARATUS 5 Sheets-Sheet 5Filed Jan. 27, 1954 T W, R

w A Ry m United States Patent Oce 2,763,041 Patented Sept. 18, 1956AUTOMATIC CASTING APPARATUS Robert Doat, Liege, Belgium ApplicationJanuary 27, 1954, Serial No. 406,450

Claims priority, application Belgium August 12, 1949 19 Claims. (Cl.2265) The present invention relates to automatic casting machines whichare used to form an object of a desired shape from a liquid materialwhich solidifies upon cooling. For example, the present invention isapplicable to machines for automatically casting seamless pipe.

This application is a continuation-in-part of copending U. S.application Serial No. 178,593, filed August 10, 1950, and entitledAutomatic Centrifugal Casting Machine, now abandoned.

Although automatic casting machines are known, they have serious defectswhich have not been overcome up to the present time. Thus, it isimpossible with the known machines to produce truly uniform products.The reason for this is that the known automatic machines can only beoperated in such a way that the parts thereof follow a predetermined,fixed, unchanging cycle. Since the material handled by the machine doesnot have fixed, unchanging properties, lack of uniformity in theproducts necessarily results. That is, the unchanging cycle of themachine parts cannot produce uniform products if, for example, thetemperature and/or viscosity of the liquid material changes, and it isimpossible to avoid such changes. For example, while the liquid materialdwells in the ladle it is necessarily cooling. This is but one exampleof unavoidable variables which cannot be taken account of by knownautomatic machines. It should be noted that the problem cannot becompletely solved by an attendant who makes adjustments because then themachine is not fully automatic, and furthermore such adjustments includeerrors necessarily inherent in human judgment. Also, adjustments of thistype are necessarily temporary.

One of the objects of the present invention is to overcome the abovedrawbacks by providing an automatic casting machine of the above typewith a means for adjusting the cycle of operations performed by theparts of the machine.

A further object of the present invention is to provide an automaticcasting machine with a means for automatically adjusting the operationsperformed by the parts of the machine.

Another object of the present invention is to automatically adjust theoperation of the machine parts to changes in the properties of thematerial handled by the machine parts so that uniformity of the productsproduced by the machine is assured.

An additional object of the present invention is to automatically adjustthe operation of the machine parts to changes in the viscosity and/ortemperature of the material handled by the machine so that changes inthese properties will not alter the uniformity of the products producedby the machine.

Still another object of the present invention is to provide an automaticcasting machine with control elements which are capable of beingautomatically moved to adjust the operation of the machine to changes inthe properties of the material handled by the machine.

A still further object of the present invention is to provide anautomatic casting machine which is capable of continuously repeatingcycles of operation while automatically adjusting the operation of theparts to variations in the properties of the material handled by themachine.

A still additional object of the present invention is to provide anapparatus capable of accomplishing all of the above objects and made upof simple and ruggedly constructed parts which are relativelyinexpensive to manufacture and which will give reliable service for along period of time.

With the above objects in view, the present invention mainly consists ofan automatic casting machine for forming an object of desired shape froma liquid material which solidifies upon cooling, this machine includinga plurality of machine elements which constitute a casting machineproper. An automatic operating means is operatively connected to themachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle. A detecting means ismounted on the machine for detecting variations in the properties of theliquid material during handling thereof by the machine elements. Anadjusting means is operatively connected to the operating means foradjusting the latter to regulate the speeds and duration of operation ofthe parts, and an actuating means connects the detecting means to theadjusting means for automatically actuating the latter to compensate formaterial variations detected by the detecting means, whereby a uniformobject is automatically produced during each cycle irrespective ofvariations in the properties of the liquid material during handlingthereof by the machine.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings, inwhich:

Figs. 1a and 1b are continuations of each other and show a side,elevational diagrammatic view of a casting machine adapted to be usedwith the present invention;

Fig. 2 is a sectional view of the machine taken along line 11-11 of Fig.1a in the direction of the arrows;

Fig. 3 is a sectional view of the machine taken along line III-III ofFig. la in the direction of the arrows;

Fig. 4 is a partly sectional, partly schematic elevational view of acontrol apparatus electrically connected to the machine of Figs. 1a and1b;

Fig. 4a is an end view of one of the cams of Fig. 4;

Fig. 5 is a fragmentary, partly sectional view of a valve apparatusshown in Fig. 3; and

Fig. 6 is a sectional view taken along line VI-VI of Fig. 5 in thedirection of the arrows.

Referring now to the drawings, and more particularly to Figs. la and lb,it will be seen that the casting machine of the invention includes abase at the left end of which, as viewed in Fig. 1a, is located acarriage 16 which turnably carries the elongated hollow mold 15 which isadapted to centrifugally cast seamless pipe, although it is to beunderstood that this is but an example of the invention which is in factapplicable to machines capable of forming any liquid material into anobject of desired shape upon solidification of the liquid. A motor 16 ismounted on the carriage 16" and rotates the mold 15 about its axisthrough the belts 16 and pulleys cooperating with the latter.

A motor 18 (Fig. 2) is connected to the underside of carriage 16" anddrives a pinion 209 which meshes with a gear 209' fixed to the shaft 210which is rotatably its operative position.

supported at the underside of the carriage 16". A pair of gears 211 and212 are also fixed to the shaft 210 and respectively mesh with gears211' and 212' which are respectively connected to the wheels 207 and207' which turnably support the carriage 16" on the inclined base. As isevident from Fig. 1a, a pair of additional wheels 208 and 208' supportthe carriage 16" for movement along the base. Thus, when motor 18 isoperating, a drive will be transmitted to the wheels 207 and 207 fordriving the carriage 16" along the base.

Liquid material is supplied to the interior of mold through the channels8 and 9 which are alternately located in an operating position, in amanner described below, so that while one channel is being used theother channel is cooling and is being made ready for use. In Figs. 1a,112 and 3 the channel 8 is shown in the operating position, while thechannel 9 is shown in its rest position.

A frame 205 is fixed to the front end of the carriage 16" and extendsforwardly therefrom along the opposite outer sides of the base, as isevident from Fig. 2. The uppermost portion of frame 205 carries theroller and guide assembly 301 for guiding the channels 8 and 9 toguarantee that the latter are located along the central axis of mold 15when the latter together with carriage 16" is located to the right ofthe position shown in Fig. 1a with one of the channels 8 or 9 extendinginto the interior of the mold 15.

On each side of the base, the frame 205 carries a reservoir 20 whichholds a cooling material for cooling the channels. Thus, the right handreservoir 20, as viewed in Fig. 2, is adapted to cool the channel 9,when the latter is in its rest position, as shown in Figs. la-3, and theleft hand reservoir 20, as viewed in Fig. 2, is adapted to cool thechannel 8, when the latter is in its rest position. Each reservoir 20communicates with a flexible conduit 20 which is adapted to supply afluid under pressure to the reservoir 20 for forcing the coolingmaterial therefrom. An electrically operable valve 37 is connected intothe conduit 20 for controlling the flow of fluid under pressure to thereservoir 20, and the circuit of electric valve 37 is adapted to beclosed and opened by a switch 36. The switch 36 on the right hand sideof the machine, as viewed in Fig. 2, cooperates with a rail 206 fixed tothe outer right side of the base, while the switch 36 on the left sideof the machine, as viewed in Fig. 2, cooperates with a rail 206identical with rail 206 and fixed to the opposite side of the base. Asis evident from Fig. la, when the carriage 16" is in its leftmostposition, as viewed in Fig. 1a, the switch 36 is located opposite theupwardly bent left end portion of rail 206 (or 206'), and therefore theswitch 36 is open at this time. However, upon movement of carriage 16"to the right, as viewed in Fig. 1, both switches 36 will engage therails 206 and 206', respectively, and will therefore be closed.

It is necessary therefore to make certain that the circuit to only oneof the valves 37 is completed, since, when channel 8 is in its operatingposition as shown in the drawing the left reservoir 20, as viewed inFig. 2, should not be operated. Therefore, a switch assembly 46 ismounted on each side of the base to be engaged and closed by one of thechannels 8 or 9 when it is in its rest position. It will be seen fromFig. lb that the upper switch 46 of switch assembly 46 is connected inseries with switch 36 so that valve 37 will only be energized whenswitch 46 is closed. Thus, with the position of the parts shown in Figs.1-3 the valve 37 located adjacent channel 9 will only be energized sincethe switch assembly 46 on the left side of the machine, as viewed inFigs. 2 and 3, is necessarily open because the channel 8 is in As willbe pointed out below, when the channel 8 is moved down to its restposition at the left side of the machine, as viewed in Figs. 2 and 3,the channel 9 will be located in the operating position previouslyoccupied by channel 8, and the channel 8 will close the switch assembly46 on the left side of the machine, as viewed in Figs. 2 and 3, whilethe switch assembly 46 on the opposite side of the machine will remainopen.

The liquid material which is handled by the machine is supplied from astructure (not shown) to the ladle 1' which is tiltably carried by thebase of the machine, and when the ladle 1' is tilted in acounterclockwise direction, as viewed in Fig. 1b, the liquid materialtherein flows into a channel 10 which feeds into the channel 8, or intoa channel 11 which feeds into the channel 9. Channels 8 and 10 movingtogether to and from the operating position in which these channels arelocated when the parts are in the position shown in Figs. 1b and 3, andthe chan nels 11 and 9 also move together to and from the operatingposition occupied by channels 10 and 8 when the parts are in theposition shown in the drawings.

Means are provided to alternately move channels 10 and 8, on the onehand, and 11 and 9, on the other hand, to and from this operatingposition. This latter moving means takes the form of a piston andcylinder arrangement 14 which cooperates with channels 8 and 9 and apiston and cylinder arrangement 33 which cooperates with channels 10 and11. As is evident from Fig. 3, the piston of the arrangement 14 hasopposite extensions extending slidably through the end walls of thecylinder, the latter being sealed to prevent the fluid from escapingtherefrom. These extensions are respectively integral with racks 12 and13 which respectively mesh with pinions 8' and 9' fixed to shafts,respectively, which are turnably carried on the base of the machine,these shafts in turn being respectively fixed to channels 8 and 9. Thus,upon movement of the piston and the racks 12 and 13 therewith to theright, as viewed in Fig. 3, the gears 8' and 9 will be turned in acounterclockwise direction, as viewed in Fig. 3, to move the channel 8from the operating position and to simultaneously move the channel 9 tothe operating position. Also, when the racks 12 and 13 move to the left,as viewed in Fig. 3, to the position shown in Fig. 3, the gears 8' and9' will be turned in a clockwise direction, as viewed in Fig. 3, to movethe channel 9 from the operating position and simultaneously movechannel 8 to the operating position. Conduits 411 and 412 communicatewith the interior of the cylinder at opposite sides of the piston, andfluid is fed to the conduits 411 and 412 by a valve 213, the details ofwhich are shown in Figs. 5 and 6.

Referring to Figs. 5 and 6, it will be seen that the valve 213 includesa cylindrical casing 403 which communicates at one end with a conduit413 which leads fluid at low pressure back to a tank or the like, a pumpcommunicating with this tank and feeding fiuid under pressure to theconduit 410 which communicates with the interior of cylinder 403 at acentral portion thereof. A cylindrical valve member 401 is tnrnablymounted in the casing 403 and is formed with an axial bore 404 inconstant communication with the discharge conduit 413. The bore 404 alsocommunicates with radially extending bores 405 and 406, the bore 406communicating with the conduit 412 in the position of the valve shown inFig. 5. The bores 405 and 406 are displaced 'by from each other. Thecylindrical valve member 401 is also formed with a central peripheralgroove 407 communicating with axially extending grooves 408 and 409,these latter grooves 408 and 409 respectively being angularly alignedwith the bores 406 and 405. Thus, the groove 408 communicates withconduit 411 when bore 406 communicates with conduit 412, as shown inFig. 5, and at the same time axial groove 409 communicates with conduit410 to receive fluid under pressure therefrom. Thus, with the valve inthe position shown in Figs. 5 and 6, the fluid under pressure flowsalong conduit 411 'into the left end of the cylinder of the arrangement14, and fluid simultaneously discharges through conduit 412 to conduit413, so that this position of the valve causes racks 12 and 13 totedisplaced to the right, as viewedin Fig. 3, which will result inmovement of channel 8 from its operating position and channel 9 to itsoperating position. If the valve member 401 is turned through 90, theflow of pressure fluid to and from the arrangement 14 is cut ofi,whereas if the valve 401 is turned through an additional 90, bore 405communicates with conduit 411 and groove 409 communicates with conduit412 to move racks 12 and 13 to the left, to the position shown in Fig.3. The valve member 401 is fixed to an end of a shaft 402 which isturned by a motor 217 through the speed-reducing transmission means 219(Fig. 3).

The piston and cylinder arrangement 33 operates in the same way asarrangement 14. The piston of-arrangement 33 is connected to a rod 331which is fixed to a rack 332 which meshes with gears and 11'respectively fixed to shafts which also are supoprted for rotation onthe base of the machine. These latter shafts are in turn fixed to thechannels 10 and 11, in the manner most clearly shown in Fig. 3. Thus,upon movement of the piston of the arrangement 33 to the left, as viewedin Fig. 3, channel 10 will be moved from the operating position shown inFi g. 3 and the channel 11 will be moved to this operating position,whereas when this piston moves to the right, as viewed in Fig. 3,channel 10 will be moved to the operating position and channel 11 willbe moved from this operating position. The operations of the piston andcylinder arrangements 14 and 33 are synchronized so that channels 8 and10 move together and so that channels 9 and 11 move together in themanner described above. The piston and cylinder arrangement 33 iscontrolled by valve 214 identical with valve 213 described above. Theconduits 410413 cooperate with valve 214 and arrangement 33 in the sameway that the conduits having these same reference characters cooperatewith valve 213 and arrangement 14. The valve member of valve 214 is alsoturned by a shaft 402', this latter shaft 402 being driven by the motor218 through the speedreducing transmission 220.

The ladle 1' is fixed to the horizontal shaft 202 which is turnablycarried on the base, and a sprocket wheel is fixed to shaft 202 andcooperates with a sprocket chain 204 which is driven by the motor 201through the speed-reducing transmission 203 (Fig. 3).

At the left end of Fig. la is shown an extracting bar 19 which isadapted to be moved into and out of the left end of mold 15 for removingtherefrom a finished seamless pipe. The structure for moving andoperating the bar 19 forms no part of the present invention.

A tube 241 is fixed to the outer surface of channel 8, and a tube 242 isfixed to the outer surface of channel 9, these tubes being perforated attheir left end portions, as viewed in Fig. la, and being adapted todistribute a powder against the inner face of the mold 15 just prior tocontact of the liquid material with the inner face of the mold. Thetubes 241 and 242 move together with the channels 8 and 9, respectively,and are respectively connected to and in communication with flexibletubes which respectively communicate with containers 41 and 40 whichhold the powder which is distributed against the inner surface of themold 15. As is evident from the right hand portion of Fig. lb, fluidpressure lines communicate with the containers 40 and 41, andelectrically operated valves 38 and 39 are respectively located in thefluid pressure lines leading to containers 40 and 41, respectively. Asis evident from Fig. l, the switch assembly 46 which cooperates withchannel 9 includes a switch 46" which is closed when channel 9 is in itsrest position for completing a part of an electrical circuit to thevalve 39 so that when the remainder of this circuit is closed, in amanner described below, valve 39 will be opened so that powder will bemoved along the tube 241 to be distributed to the inner face of the mold15. In the same way, the switch assembly 46 on the opposite side of thebase cooperates with channel 8, when the latter is in its rest position,to close part of a circuit to the valve 38 which, when energized, admitsfluid under pressure to container 40 so that powder will be distributedfrom tube 242 to the inner face of the mold when channel 9 is in itsoperating position. This powder may be Fe-Si powder, as is well known inthe art.

All of the above-described structure constitutes a casting machineproper. The present invention includes a control apparatus forautomatically operating the parts of the casting machine proper in apredetermined sequence, for predetermined durations and at predeterminedspeeds, during each of a number of cycles which may be indefinitely andautomatically repeated by the machine. This structure for thusautomatically operating the parts of the casting machine proper is shownin Fig. 4. Referring to Fig. 4, it will be seen that the controlapparatus includes a support on which the shaft 7 is turnably mounted,this shaft 7 being driven by the motor 7 through a governor of any knownconstruction which guarantees that the shaft 7 will rotate at a constantspeed which may be set by adjustment of the governor, as is well known.The apparatus may be stopped and started by opening and closing,respectively, the switch 21 shown in Fig. 4. The shaft 7 carries cams1-6 which are mounted on the shaft 7 for rotation therewith, these camsrespectively cooperating with six cam followers mounted forreciprocating movement on the support of the control apparatus and beingurged by coil springs toward the cams 1 6, respectively, as is evidentfrom Fig. 4. The followers which cooperate with cams 1, 2 and 6 arerespectively operatively connected to variable resistors 1", 22, and 6'.

The variable resistor or potentiometer 1" is electrically connected tothe lines 24 leading to the motor 201 which controls the tilting of theladle 1. The motor 201 is an induction motor, and two of the leadsenergize the field or stator windings thereof while the other two leadsenergize the rotor or armature windings thereof. Although thepotentiometer 1" may by itself regulate the speed and direction ofrotation of the motor 201, in the example illustrated the potentiometer1" is connected to an electronic installation A which includes suchelements as thyratrons the voltage of which is controlled by thepotentiometer 1", this voltage being applied to the grids of thethyratrons which thus proportionally vary the anode currents of thethyratrons. Through the medium of electro-magnetic relays, thesevariable anode currents regulate the value and direction of currentinduced in the motor 201 so that the speed and direction of rotation ofthe latter is controlled by the cam 1.

In the same way the cam 2 controls the variable resistor 22 whichthrough the electronic installation B, similar to the electronicinstallation A, controls the speed of rotation of motor 16, as well asthe stopping and starting thereof through the electrically conductiveleads 23, the motor 16 being similar to the motor 201. The variableresistor 6 is controlled by the cam 6 to operate the motor 18 throughthe electrically conductive leads 26 and the electronic installation C,which, in the same way as was described above in connection with motor201, control the speed and direction of rotation of the motor 18.

The follower which cooperates with cam 3 opens and closes the switch 215which through the electrically conductive leads 28 stops and starts themotor 217 to turn the valve member of valve 213 periodically through sothat the flow of fluid pressure to and from the cylinder and pistonarrangement 14 is regulated to move the channels 8 and 9 in the mannerdescribed above. In the same way the follower which cooperates with cam4 closes and opens a switch 216 which through the electricallyconductive leads 27 stops and starts the motor 218 for operating valve214 in synchronism with valve 213.

The follower which cooperates with cam 5 opens and closes a switch 217which through the electrically conductive leads 25 opens and closes acircuit to the valves new;

38 or 39, depending on which of the channels 8 or 9 is in its restposition. As was mentioned above, when channel 9 is in its restposition, as shown in the drawings, the circuit will be completedthrough valve 39 for distributing powder from tube 241 against the innerface of mold 15, while when channel 8 is in its rest positiot thecircuit will be completed through valve 38 for distributing powderthrough tube 242 to the inner surface of mold 15.

The structure of the invention as thus far described, is capable ofcontinuously and cyclically operating the parts of the casting machineproper to produce a seamless pipe during each cycle. The operationswhich take place during one cycle are the following:

With the parts in the position shown in Fig. 1, let it be assumed that acompleted part is about to be extracted from the mold 15 and that theoperations for the manufacture of another pipe are about to commence. Atthis moment the extracting bar 19 is at a certain distance from themold. The movement of bar 19 is independently controlled by pressing abutton which is not a part of the machine itself. The mold is stationaryand the carriage rests at the lowermost left hand portion of the base,as viewed in Fig. 1a. The ladle is stationary. It is supplied withmaterial by structure independent of the machine and not shown in thedrawings. All that is required is that the ladle 1' be filled with adesired quantity of liquid material at the moment when the carriage 16has arrived at the rightmost point of its travel along the base of themachine, as viewed in Fig. 1b.

The shaft 7 which carries the cams rotates at a constant speed evenwhile the parts of the casting machine proper are at rest, the camshaving circular portions which do not move the followers during thistime. During this stationary period of the casting machine proper, thefinished pipe is removed by the extracting bar 19. When the mold is isempty, the shaft 7 has turned through an angle sutficient to cause thecam 6 to actuate the follower associated therewith for energizing motor18 to drive the carriage 16", and all parts carried thereby, up the baseof the casting machine to the right, as viewed in Fig. 1a. During thismovement of the carriage 16" the channel 8 is received into the guidemeans 301 and into the mold 15 which continues to envelop the channel 8to an increasing extent as the carriage 16" moves to the right, asviewed in Fig. 1. Also, during this movement of carriage 16", the rightswitch 36, as viewed in Fig. 2, is closed by the stationary rail 206 sothat: cooling material is sprayed from the right reservoir 20, as viewedin Fig. 2, against the inner face of channel 9, and as the carriage 16continues to move to the right, the reservoir 20 moves therewith so thatthe cooling material is distributed along the entire inner surface ofchannel 9. As was mentioned above, the left reservoir 20, as viewed inFig. 2, cannot operate at this time because the left switch assembly 46is open. Only the right switch assembly 46 is closed because channel 9is located in its rest position. At a predetermined moment during themovement of the car riage 16" up the base, the cam 2 actuates itsfollower to start rotation of motor 16 so as to rotate the mold 15 andduring movement of the carriage the speed of rotation of the mold isincreased until it is rotating at full speed at the moment when thecarriage 16" arrives at the end of its advancing movement along the baseto the right, as viewed in Figs. la and 1b, the mold 15 continuouslymoving along and surrounding the channel 8 and the channel 9 beingcontinuously cooled along its length during this time.

When the carriage has arrived at its rightmost pdsition, as viewed inFig. lb, the switch 36 opens due to the upwardly curved right endportion of rail 206, as viewed in Fig. 1, so that the cooling of channel9 stops at this time. The mold 15 continues to rotate. The ladle 1' isfilled with molten material ready to be poured into the mold, and atthis moment the cam 1 actuates its follower to energize motor 201 fortilting the ladle forwardly. The liquid material flows along channels 10and 8 toward the left end of the latter, as viewed in Fig. 1b, fromwhich the material falls onto the inner surface of the rotating mold.The cam 5 closes the circuit through valve 39 just prior to arrival ofmolten metal at the inner surface of the mold, so that Fe-Si powder isdistributed against the rotating inner surface of mold 15 just beforethe molten metal drops from channel 8 onto the rotating mold 15. The cam6 then actuates motor 18 to reverse the movement of the carriage 16" sothat the latter now moves to the left, as viewed in Fig. lb, toward theleft end position shown in Fig. 1a, and during this leftward movement ofthe carriage and rotating mold 15 therewith, Fe-Si powder continues tobe distributed against the inner surface of the mold and molten materialcontinues to fall against the inner surface of the mold which uncoverschannel 8 to an increasing extent during this part of the cycle.

At a predetermined point during the return of carriage 16'', the cam 1actuates motor 201 to return the ladle 1' to its rest position. If theladle 1 holds only enough molten material for one pipe, then the speedof the return movement of the ladle 1 is of no consequence. However,when the ladle 1' holds an amount of molten material suflicient for aplurality of pipes, the cam 1 is shaped to quickly return the ladle 1'so as to sharply cut off the flow of molten material therefrom.

Shortly after the liquid material has stopped flowing from ladle 1', thecam 5 opens the circuit through valve 39 to stop the distribution ofFe-Si powder.

When the carriage 16 and guide means 301 are completely-separated fromchannel 8, the cams 3 and 4 actuate valves 213 and 214 to reversechannels 8 and 9 together with channels 10 and 11, respectively, so thatchannels 11 and 9 assume the position previously occupied by channels 10and 8, as was described above. The cam 2 stops the rotation of the moldafter a time sufficient for the material therein to solidify, and thus acycle of operations is completed. During the next cycle, the electricvalve 38 will be energized and channels 11 and 9 will guide the materialto the mold, while channel 8 is cooled on the opposite side of themachine.

The structure of the invention as thus far described is thereforecapable of continuously operating to produce a plurality of seamlesspipes one after the other in a fully automatic manner. However, itshould be noted that the structure described above will be incapable ofproducing uniform pipes. Among the reasons for this are the following:

As the material dwells in the ladle 1', it cools and its viscositychanges. The rate of cooling is not uniform since it is a well knownfact that the molten material will cool at a much faster rate when itfirst becomes located in the ladle, and this rate of cooling thendecreases.

Furthermore, where the ladle 1 holds an amount of material which issuflicient for more than one pipe, it is evident that the several pipesmade from the charge held by ladle 1' will be made from molten materialhaving dilferent temperatures and viscosities. Furthermore, it isdifiicult to control and predict the rate of flow of the material alongthe channels. Thus, it is inevitable that variable factors will arisewhich will prevent uniformity in the products produced by the apparatus,and where the parts of the casting machine proper are controlled so asto operate in a fixed, unchanging manner through several cycles, it isevident that lackof uniformity in the products will necessarily result.

The present invention includes a means for overcoming the latterdrawbacks in a 'fully automatic manner which is uninfiuenced by errorsinherent in human judgment. Thus, it will be seen that the cams 1, 2 and6 have camming surface portions which vary along the axis of the cams.Fig. 4a shows a cam 29 which may be used for one of the cams 1, '2 or 6.It is possible 'to machine the 9 carnming surfaces of these cams so thatthey; will control the apparatus according to predetermined lawsrequired by variations in the temperature and viscosity of the material,or, as is shown in Figs. 4 and 4a, each of the cams 1, 2 and 6 may bemade up of a plurality of individual cam portions which are groupedtogether and angularly fixed to each other to rotate as a unit. Thecamming surface portions of the several cam portions smoothly merge intoeach other so that the followers will have no difliculty in cooperatingwith a shifting cam. In the particular embodiment disclosed in Fig. 4,the several cam portions of each cam are keyed together to a sleevewhich is slidably keyed on the shaft 7 so that each of the cams 1, 2 and6 is constrained to rotate with shaft 7 while being slidable therealong.As is shown in Fig. 4, the shaft 7 may be provided with notchescooperating with a spring connected to each cam for positively locatingthe cam in one of a number of positions along the shaft 7.

The support of the control apparatus shown in Fig. 4 includes a meansfor guiding and supporting the substantially U-shaped shifting members104, 106 and 108 for movement along a path parallel to the shaft 7,member 104 embracing an edge portion of cam 1, member 106 embracing anedge portion of cam 2, and member 108 embracing an edge portion of cam6. Each of the shifting members is formed with a rack portion, and theserack portions respectively mesh with pinions driven by motors 105, 107,and 109, respectively. Thus, motor 105 may be operated to shift member104, motor 107 may be operated to shift member 106, and motor 109 may beoperated to shift member 108.

According to the present invention means are provided for detectingvariations in properties of the molten material, such as the temperatureand viscosity thereof, and this detecting means sends impulses to anelectronic apparatus which evaluates and amplifies the impulses andwhich is electrically connected to the motors 105, 107 and 109 forautomatically operating the latter in a manner which automaticallyadjusts the cams 1, 2 and 6 to variations in the properties of theliquid material, such as the temperature and viscosity thereof.

Thus, referring to Figs. la and 1b, it will be seen that a photoelectriccell 102 is arranged opposite the operating position of channels 10 and11 to be influenced by light rays emanating from the molten materialflowing down either of these channels. Also, an additional photoelectriccell 101 is located opposite the left end of mold 15 to be influenced bylight rays emanating from molten material located in the mold 15. Thephotoelectric cell 101 is carried by a lever which is mountedintermediate its ends on the left end of carriage 16" for tiltingmovement about the pivot pin 221. Thus, the photoelectric cell 101 movestogether with the carriage 16". A support 231 is fixed to the base,extends upwardly therefrom and carries at its upper end a pin 230 whichis located above pin .221 in the path of movement of the lever carryingphotoelectric cell 101, as carriage 16" moves to the left, as viewed inFig. 1a, back to its rest position. Therefore, just before the carriage16" reaches its rest position, the lever carrying cell 101 will movewith respect to pin 230 to cause the latter to tilt cell 101 in aclockwise direction about pivot 221 to the position shown in solid linesin Fig. la, so that the cell 101 does not interfere with the operationof the pipe extracting bar 19. When the carriage 16" is located anywhereto the right of a position located slightly to the right of that shownin Fig. 1a, the photoelectric cell 101 will by gravity automaticallyassume the position shown in dot-dash lines so that it will beinfluenced by light rays emanating from molten material located in themold 15. The leads connected to photocell 101 are of course flexible soas not to interfere with the tilting movement of the cell. Thus, thecell 102 will be influenced by the molten material at a time intervalprior to influence of cell 101 by the molten material, so that the cells101 and 102 can measure the rate of flow of the :10 molten material andtherefore give an indication of viscosity thereof.

Furthermore, a pyrometer 120 is fixed to the top of ladle 1' and extendsinto the latter to measure the temperature of the molten material, theelectrical leads to the pyrometer also being flexible so that thepyrometer is free to tilt with the ladle 1. The impulses received by anddelivered from photocells 101 and 102 and pyrometer 120 are sent to anelectronic installation 103 similar to the electronic installation Adescribed above. The electronic installation 103 evaluates and amplifiesthe impulses received from elements 101, 102, and 120 and iselectrically connected by lines 111, 112, and 113 to the motors 109,107, and 105, respectively, and the electronic apparatus 103 is suppliedwith current by the lines which are connected to any source ofalternating current. Thus, the motors 105, 107, and 109 areautomatically operated to shift cams 1, 2 and 6, respectively, in amanner which automatically adjusts these cams to variations in theproperties of the material handled by the machine, and in this way it ispossible with the apparatus of the invention to produce uniform productsin a fully automatic manner. Thus, without the detecting means, of theinvention, the electronic installation for evaluating and amplifying theimpulses received from the detecting means, and the structure operatedby this electronic installation for shifting the cams 1, 2, and 6, itwould not be possible to produce uniform products. For example, if theladle is tilted during each cycle through the same angle and at the samespeed and if the carriage 16" moves back to its rest position at thesame speed during each cycle, it is evident that as the temperature ofthe molten material decreases and the viscosity thereof increases lessmolten material will flow from the ladle and the distribution of themolten material along the mold will necessarily vary from cycle tocycle. With the structure of the invention, however, the ladle is tiltedto a greater degree and held tilted for a longer period of time in afully automatic manner as the temperature of the material drops, thiscontrol being derived from the pyrometer, and also the rate of movementof the carriage 16" back to its rest position is decreased in a fullyautomatic manner as the viscosity of the molten material increases, thislatter control being derived from the photoelectric cells, so thatabsolute uniformity of the products is assured with the structure of theinvention.

It should be noted that the above described details of the detectingmeans may be varied. For example, instead of the photoelectric cells, itis possible to arrange switches along the path of flow of the moltenmaterial, these switches having movable arms entrained by the flowingmaterial to successively close the switches so that the time intervalbetween closing of successive switches gives an indication of theviscosity of the material. Also, the flowing material might entrain amovable member which actuates a variable resistor to indicate theviscosity of the material. Or, it is possible to measure the distancetravelled by an object which melts at a predetermined known temperaturein order to determine the viscosity and/or temperature of the material.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofcasting machines differing from the types described above.

While the invention has been illustrated and described as embodied inautomatic centrifugal casting machines, it is not intended to be limitedto the details shown, since various modifications and structural changesmay be made without departing in any way from the spirit of the Dresentinvention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art,- fairly constitute essentialcharacthe 1 1 teristics of the generic or specific aspects of thisinvention and, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence ofthe followingclaims.

What is claimed as new and desired to be secured by Letters Patent is:

1. An automatic casting machine for forming an object of desired shapefrom a liquid material which solidifies upon cooling, comprising, incombination, a plurality of machine elements constituting a castingmachine proper; automatic operating means operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle; detecting meansmounted on the machine for detecting variations in the properties of theliquid material during handling thereof by said machine elements;adjusting means operatively connected-to said operating means foradjusting the latter toregulate said speeds and durations; and actuatingmeans connecting said detecting means to said adjusting meansforautomatically actuating the latter to compensate for materialvariations detected by said detecting means, whereby a uniform object isautomatically produced duringeach cycle irrespective of variations intheproperties ofthe liquid material during handling thereof by the machine.

2. An automatic casting machine for forming an object of .desired shapefrom a liquid material which solidifiesupon cooling, comprising, incombination, a plurality of machine elements constituting a castingmachine proper; automatic operating means operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle; and compensatingmeans operatively connected-to said operating means for automaticallyadjusting the latter in a manner which compensates for variations in theproperties of the liquid material handled by the machine, whereby auniform object isautomatically producedduring each cycle irrespective ofvariations in the properties of the liquid material duringhandling'thereof by the machine.

;3. A machine as defined in claim land ,wherein said operating meansincludes atleast one cam memberrhaving a camming profile which variesalong the axis of said cam member and a follower member-engaging saidprofile, said adjustingmeans engaging at least one of said members forshifting the same axiallywith respect to the other of said members.

4. An automatic castingmachine for formingan object of desired shapefrom a liquid material-Which solidifies upon cooling, comprising, incombination, apluraliry of machine elements constituting a castingmachine proper; automatic operating means operatively connected to saidmachine elements for automatically,continuously and cyclically operatingthe same at predetermined speeds, for predetermined durations, and in apredetermined sequence during each cycle; detecting means mounted on themachine for detecting variations in the viscosity of the liquid materialduring handling thereof by said machine elements; adjusting meansoperatively, connected to said operating means for adjusting the latterto regulate said speeds and durations; andactuatingmeans connecting saiddetecting means to saidadjusting means for automatically actuating thelatter tocompensatefor viscosity variations detected-by said detectingmeans, whereby a uniform object is automatically'produced during eachcycle-irrespective of variations in the viscosity of the liquid materialduring handling thereof bythe machine.

5. An automatic casting machine for forming, an object of desired shapefrom a liquid material which solidifies upon cooling, comprising, incombination, a plurality of .machine elements :constituting .a casting.machine proper; automatic operating means operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle; detecting meansmounted on the machine for detecting variations in the temperature ofthe liquid material during handling thereof by said machine elements;adjusting means operatively connected to said operating means foradjusting the latter to regulate said speeds and durations; andactuating means connecting said detecting means to said adjusting meansfor automatically actuating the latter to compensate for temperaturevariations detected by said detecting means, whereby a uniform object isautomatically produced during each cycle irrespective of variations inthe temperature of the liquid material during handling thereof by themachine.

6. An automatic casting machine for forming an object of desired shapefrom a liquid material which solidifies upon-cooling, comprising, incombination, a plurality of machine elements constituting a castingmachine proper; automatic operating means operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle, said operating meansincludinga support, a shaft rotatably carried by said support,-a camhaving a camrning profile which varies along the axis of the cam mountedon said shaft for rotation therewith and for shifting movementt-herealong, and a follower engaging said cam; electrical detectingmeans mounted on the machine for detecting variations in the propertiesof the liquidimaterial during handling thereof by said machine elements;adjusting means operatively connected to said operating means foradjusting the latter to regulate said speeds and durations, at least apart of said adjusting means engaging said cam for shifting the latteralong said shaft; and actuating means connecting said detecting means tosaid adjusting means for automaticallyactuating the latter-to compensatefor material variations detected by said detecting means, whereby auniform object .is automatically produced during eachcycletirrespectiveof variations in the properties of the liquidmaterial-during handling thereof by the machine.

'7. :Arnachineas defined in claim 1 and wherein said detectingmeans'includes photoelectric cells spaced from each-other'and influenced bylight rays from the liquid maten'atto measure the speed of flow thereof.

8. .A'machine as defined in claim land wherein said detectingmeansincludes photoelectric cells spaced from eachother and influenced bylight rays from the liquid material to .measurethe speed of flowthereof, and a pyrometer for measuring the temperature of the liquidmaterial.

-.9. :An automatic casting machine for forming an object of desiredshape-froma liquid material which solidifies upon cooling, comprising,in combination, a plurality of machineeleinents-constitutinga castingmachine proper; automaticroperatingmeans operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperatingthe-same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle, said operating meansincluding asupport,-a-shaft rotatably-carried by said support, a camhaving a carnmingprofile which varies along the axis of the cam mountedon said shaft for rotation therewith and for shifting movementtherealong, and a follower engagingsaidv cam; electrical detecting meansmounted on the machinefor detecting variations in the properties of theliquid material during handling thereof by said machineelementspadjusting means operatively connected to said operatingmeans'for adjusting'the latter to regulate said speeds randudurations,at least a part of said adjusting meanszengaging saidcarn for shiftingthe latter along said shaft; and actuating means connecting saiddetecting means to said adjusting means for automatically actuating thelatter to compensate for material variations detected by said detectingmeans, whereby a uniform object is automatically produced during eachcycle irrespective of variations in the properties of the liquidmaterial during handling thereof by the machine, said actuating meansincluding an electronic apparatus for receiving impulses from saiddetecting means, for interpreting and for amplifying the impulses, andan electrical moving means operated by said electronic apparatus andconnected to said part of said adjusting means for moving said part inaccordance with said impulses.

10. An automatic casting machine for forming an object of desired shapefrom a liquid material which solidifies upon cooling, comprising, incombination, a plurality of machine elements constituting a castingmachine proper; automatic operating means operatively connected to saidmachine elements for automatically, continuously and cyclicallyoperating the same at predetermined speeds, for predetermined durations,and in a predetermined sequence during each cycle, said operating meansincluding a support, a shaft rotatably carried by said support, a camhaving a camming profile which varies along the axis of the cam mountedon said shaft for rotation therewith and for shifting movementtherealong, and a follower engaging said cam; electrical detecting meansmounted on the machine for detecting variations in the properties of theliquid material during handling thereof by said machine elements;adjusting means operatively connected to said operating means foradjusting the latter to regulate said speeds and durations, at least apart of said adjust ing means engaging said cam for shifting the latteralong said shaft; and actuating means connecting said detecting means tosaid adjusting means for automatically actuating the latter tocompensate for material variations detected by said detecting means,whereby a uniform object is automatically produced during each cycleirrespective of variations in the properties of the liquid materialduring handling thereof by the machine, said actuating means includingan electronic apparatus for receiving impulses from said detectingmeans, for interpreting and for amplifying the impulses, and anelectrical moving means operated by said electronic apparatus andconnected to said part of said adjusting means for moving said part inaccordance with said impulses, said moving means comprising a rackconnected to said part of said adjusting means, a pinion meshing withsaid rack, and an electric motor operatively connected to said pinionfor rotating the latter.

11. In an automatic casting apparatus for forming an object of desiredshape from a liquid material which solidifies upon cooling, incombination, a suport; a shaft turnably carried by said suport; drivemeans connected to said shaft for rotating the latter; a cam mounted onsaid shaft for rotation therewith and for shifting movement therealong,said cam having a camming profile which varies along the axis of saidcam; a follower engaging said cam to be moved thereby; variable resistormeans operatively connected to said follower to be operated thereby; amotor connected to a part of the apparatus for operating said part; anelectrical circuit including said motor and variable resistor means, sothat the operation of said motor is controlled by said cam and follower;shifting means engaging said cam for shifting the latter along saidshaft with respect to said follower so as to change the camming profilewhich engages said follower to thereby change the operation of saidmotor; detecting means connected to the apparatus for detectingvariations in the properties of the liquid material handled by theapparatus; and transmission means operatively connected to saiddetecting means to receive therefrom indications of property variationsin the liquid material and operatively connected to said shifting meansto transmit said indications to the latter and to operate the latter toshift 14 said cam in a manner which compensates for variations in theproperties of the liquid material.

12. In an automatic casting apparatus for forming an object of desiredshape from a liquid material which solidifies upon cooling, incombination, a support; a shaft turnably carried by said support; drivemeans connected to said shaft for rotating the latter; a cam mounted onsaid shaft for rotation therewith and for shifting movement therealong,said cam having a camming profile which varies along the axis of saidcam; .a follower engaging said cam to be moved thereby; variableresistor means operatively connected to said follower to be operatedthereby; a motor connected to a part of the apparatus for operating saidpart; an electrical circuit including said motor and variable resistormeans, so that the operation of said motor is controlled by said cam andfollower; shifting means engaging said cam for shifting the latter alongsaid shaft with respect to said follower so as to change the cammingprofile which engages said follower to thereby change the operation ofsaid motor; electrical detecting means connected to the apparatus fordetecting variations in the properties of the liquid material handled bythe apparatus; and electronic means connected to said detecting meansfor receiving, interpreting, and amplifying impulses received from saiddetecting means, said electronic means being operatively connected tosaid shifting means for operating the latter in accordance with impulsesreceived from said detecting means, whereby the operation of said motoris automatically adjusted to variations in the properties of the liquidmaterial.

13. In an automatic casting apparatus for forming an object of desiredshape from a liquid material which solidifies upon cooling, incombination, a support; a shaft turnably carried by said support; drivemeans connected to said shaft for rotating the latter; a cam mounted onsaid shaft for rotation therewith and for shifting movement therelong,said cam having a camming profile which varies along the axis of saidcam; a follower engaging said cam to be moved thereby; variable resistormeans operatively connected to said follower to be operated thereby; amotor connected to a part of the apparatus for operating said part; anelectrical circuit including said motor and variable resistor means, sothat the operation of said motor is controlled by said cam and follower;a U- shaped shifting member embracing an edge portion of said cam andbeing mounted on said support for movement along a path parallel to saidshaft; rack means connected to said shifting member for movementtherewith; a pinion meshing with said rack means; a second motorconnected to said pinion to rotate the latter; electrical detectingmeans connected to the apparatus for detecting variations in theproperties of the liquid material handled by the apparatus; andelectronic means operatively connected to said detecting means forreceiving, interpreting, and amplifying impulses of said detecting meansand being operatively connected to said second motor for operating thelatter in accordance with said impulses, whereby said shifting member isautomatically moved along said path to shift said cam for automaticallyadjusting the operation of said first-mentioned motor to variations inthe properties of the liquid material handled by the apparatus.

14. In an apparatus as defined by claim 13, said apparatus includingguide means for guiding the liquid material along a predetermined pathand said detecting means including a pair of photoelectric cells locatedopposite spaced portions of said guide means to be influenced by lightrays emanating from the liquid material for measuring the speed of flowof the liquid material so as to detect variations in the viscositythereof.

15. In an apparatus as defined by claim 13, said detecting meansincluding a pyrometer adapted to engage 15 the liquid material fordetecting variations in the temperature thereof.

16. In an apparatus for automatically forming objects of a desired shapefrom a liquid material which solidifies upon cooling, in combination, anelongated base; a carriage mounted on said base for movement therealong;a first motor operatively connected to said carriage for driving thelatter along said base; an elongated hollow mold turnably carried bysaid carriage; a second motor also carried by said carriage and beingoperatively connected to said mold for rotating the latter on saidcarriage; a ladle tiltably carried by said base and being spaced fromsaid carriage; a third motor operatively connected to said ladle fortilting the latter; channel means carried by said base and located atone end next to said ladle to receive liquid material therefrom; anelectrical circuit connected to said first, second and third motors forenergizing the same and including first, second, and third variableresistors respectively connected electrically to said first, second andthird motors for controlling the operation thereof; first, second, andthird cam followers operatively connected to said first, second andthird variable resistors, respectively, for operating the latter;support means movably supporting said followers; first cam meansengaging said first follower for moving the latter to operate said firstvariable resistor in a manner which operates said first motor to drivesaid carriage up to said channel means to locate said mold in a positionto receive liquid material from said channel means and away from saidchannel means after liquid material is located in said mold, duringrotation of said first cam means, the latter having a camming profilewhich varies along the axis of said first cam means; second cam meansengaging said second follower for moving the latter to operate saidsecond variable resistor in a manner which operates said second motor torotate said mold until the liquid material solidifies in said mold,during rotation of said second cam means, the latter having a cammingprofile which varies along the axis of said second cam means; third cammeans operatively engaging said third follower to move the latter tooperate said third variable resistor in a manner which operates saidthird motor to tilt said ladle when said carriage is in said position,for delivering liquid material to said channel means to be received bysaid mold, during rotation of said third cam means, said third cam meanshaving a camming profile which varies along the axis of said third cammeans; a shaft turnably carried by said support means and carrying saidfirst, second and third cam means for rotation with said shaft and forshifting movement along said shaft; drive means connected to said shaftfor rotating the latter; first, second and third electrical shiftingmeans respectively located next to said first, second and third cammeans for shifting the latter along said shaft; electrical detectingmeans mounted on the apparatus for detecting variations in theproperties of the liquid material handled by the apparatus; andelectronic means electrically connected to said detecting means forreceiving impulses therefrom and for interpreting and amplifying saidimpulses and being electrically connected to said f rst, second andthird shifting means for automatically operating the latter inaccordance with impulses received from said detecting means toautomatically shift said first, second and third earn means along saidshaft for automatically adjusting the operation of said first, secondand third motors to variations in the properties of'the liquid material,whereby uniform objects are automatically produced by the apparatusirrespective of variations in the properties of the liquid material.

17. In an apparatus as defined in claim 16, said channel meanscomprising a pair of elongated channel portions located next to eachother; electrically operable moving means operatively connected to saidchannel portions for alternately moving the latter to and from anoperating position; a switch electrically connected to said moving meansfor opening and closing a circuit to the latter; a fourth followeroperatively connected to said switch for closing and opening the latterand being mov ably carried by said support means; and fourth cam meanscarried by said shaft for rotation therewith and engaging said followerfor moving the latter in a manner which operates said moving means tomove one of said channel portions to said operating position and theother or" said channel portions away from said operating position aftera cycle of operations is completed.

18. In an apparatus as defined in claim 17, and a cooling means carriedby said carriage for cooling each channel portion when it is out of saidoperating position thereof.

19. In an apparatus as defined in claim 16, said apparatus including anelectrically'operable distributing means connected into said electricalcircuit for distributing a powder against the inner surface of saidmold; a switch electrically connected to said distributing means foropening and closing a circuit to the latter; a fourth followeroperatively connected to said switch for closing and opening the latterand being movably carried by said support means; and fourth cam meanscarried by said shaft for rotation therewith and engaging said followerfor moving the latter in a manner which operates said distributing meansto apply powder to the inner surface of said mold just prior to thearrival of liquid material at the inner surface of said mold.

References Cited in the file of this patent UNITED STATES PATENTS1,746,374 Uhrig Feb. 11, 1930 1,762,177 Ladd June 10, 1930 1,783,094Moore etal Nov. 25, 1930 2,000,155 White May 7, 1935 2,206,930 WebsterJuly 9, 1940 2,225,373 Goss Dec. 17, 1940 2,274,565 Start et a1 Feb. 24,1942 2,526,753 Huck Oct. 24, 1950 2,532,256v Holmes et al. Nov. 28, 19502,586,713 Ratcliffe et al. Feb. 19, 1952 2,682,691 Harter July 6, 1954

